$\dfrac{5}{3} - \dfrac{8}{5} = {?}$
Explanation: $ = {\dfrac{5 \times 5}{3 \times 5}} - {\dfrac{8 \times 3}{5 \times 3}} $ $ = {\dfrac{25}{15}} - {\dfrac{24}{15}} $ $ = \dfrac{{25} - {24}}{15} $ $ = \dfrac{1}{15}$